Examples of a display device such as a liquid-crystal display device which is being developed include a touch panel integrated display device that has a touch panel (an area sensor) function of detecting (i) a position in a panel surface which position is touched with an input pen emitting visible light and (ii) color information of the visible light.
For example, Patent Literature 1 discloses an image pickup apparatus which uses, as a light sensor element, an image sensor having a CMOS structure, so as to discriminate a light source, an object, etc., which emits light of different wavelengths. According to the image pickup apparatus disclosed in Patent Literature 1, a pixel of a color filter which has a specific light transmittivity is selectively read while a pixel signal is being read from a pixel array section in which color filters are provided for respective pixels in a given pattern, and a signal intensity of the read pixel is determined, so that a color of the light which is emitted from the light source, the object, etc. is determined.